What kind of water do vegetables "prefer"?

1. Issues derived from vegetables

We all need to eat vegetables, because vegetables are rich in nutrients, and the taste of some vegetables is also Very good, good for our growth and development. However, we don’t know or understand the growing process of vegetables, and we want to grow vegetables ourselves. So, what to plant? What are you studying? On hot days, we sometimes drink mineral water and sometimes boiled water. Are vegetables the same as us? Is it better to drink mineral water or tap water? Most of us think that tap water is good for watering vegetables, but a few people think that mineral water is good for watering vegetables, and some people think that any water can be used for watering. In order to prove which type of watering vegetables is better, Teacher Wang selected sixteen people including me and Li Han, Miao Rui, Zhang Dongxu to study this problem.

2. If you want to research, make a plan first

After making the decision to grow vegetables, we are all gearing up and eager to try. We wish we could grow a variety of vegetables immediately so that we can take a look at them. What was it like when you were a child? How did you grow up? Do you prefer to drink tap water, mineral water, or both? Those of us who have experienced several comprehensive practical activities must first discuss a plan and determine the activity plan.

First of all, we set up a plant research experimental team. Li Han, Miao Rui, Zhang Dongxu and I served as temporary team leaders. Each of our team leaders led three team members. The group I led planted chrysanthemum, Li Han's group planted coriander, Miao Rui's group planted spinach, and Zhang Dongxu's group planted Chinese cabbage. First, each group searched for detailed information about vegetables on the Internet to understand the living habits and cultivation techniques of the vegetables they wanted to grow; then Miao Rui prepared flower pots; Yang Fan was responsible for preparing humus-rich loam; Li Han and Zhang Dongxu were responsible for preparing farmyard manure as base fertilizer; Seeds are solved by each group on their own. Then we decided to personally plant vegetables and conduct research using comparative experiments. Each group planted two pots of the same vegetables. The soil, pots, vegetables, watering volume, etc. were all the same. Only one pot was filled with mineral water and the other with tap water. It was required that every time Water the same amount, and then observe and record the growth of the vegetables to see what results will occur.

Teacher Wang also asked us to divide work and cooperate. We should not only work hard to complete the tasks of our group, but also take advantage of various opportunities to pay attention to learning vegetable growing techniques.

3. Search for information with a purpose

We read the most basic methods of growing these vegetables on the Internet. It is very simple: after leveling the ground and raking it finely, first grab some Spread a small handful of seeds evenly on the soil, push the seeds into the soil about five millimeters, and water them once every two or three days.

I also read some vegetable information:

Chrysanthemum chrysanthemum: (also known as basil, spring chrysanthemum, mugwort stalk) Asteraceae, one or two-year herbaceous plant, native to China and Mediterranean region. The number of chromosomes is 2n=2x=18. It has a special smell and is rich in nutrients. Traditional Chinese medicine believes that chrysanthemum has the effects of clearing blood, nourishing the heart, lowering blood pressure, moistening the lungs, and clearing phlegm. It is often used as a flower bed flower in Europe. Chrysanthemum chrysanthemum is divided into two types according to the size of its leaves: large-leaf chrysanthemum and small-leaf chrysanthemum. Large-leaf Chrysanthemum, also known as Platyleaf Chrysanthemum or Round-leaf Chrysanthemum, has broad leaves, few and shallow notches, thick leaves, short and thick twigs, less fiber, good quality, and high yield, but it grows slowly and matures slightly late. It is more commonly cultivated. . Small-leaf chrysanthemum, also known as mosaic chrysanthemum or fine-leaf chrysanthemum, has narrow leaves, many and deep chromosomes, thin leaves, but strong fragrance, thin twigs and fast growth. It has poor quality, low yield, cold tolerance, earlier maturity and less cultivation. This type has been cultivated in Beijing into a variety for tender stems - Artemisia spp. Chrysanthemum chrysanthemum prefers cold weather and cannot tolerate high temperatures. The optimum temperature for growth is around 20°C. Growth is slow below 12°C and poor growth above 29°C. Sowing can be done in both spring and autumn, with autumn sowing having a longer growing period and higher yields. Chrysanthemum chrysanthemum has small plants and a short growing season, so it can be intercropped with other vegetables. Use more direct seeding, and use 3-4kg of seed per acre (autumn sowing). Seedlings and transplants are also practiced in a few places such as Guangzhou. After the autumn chrysanthemum is sown, it needs to be watered every day before it emerges from the ground to keep the soil moist. The spring chrysanthemum should be covered with a film to prevent cold. About 35 days after the autumn chrysanthemum is unearthed, the seedling height is 14-16cm. Large plants can be harvested in batches. Spring chrysanthemum is easy to bolt and should be harvested in time before bolting. However, Beijing uses highly dense planting and harvests later, after bolting and before buds appear. Chrysanthemum chrysanthemum seeds are mostly collected in spring sowing fields to select strong seeds with the characteristics of this variety. The spacing between rows is 30cm square. It blooms from April to May and the fruits mature in early June. There is also a method to choose a sheltered and sunny place in autumn and select high-quality seeds to save seeds. This method is effective in improving the quality, cold resistance and late bolting of Chrysanthemum chrysanthemum.

Spinach (also known as spinach, Persian grass, red root) belongs to the Trichosanthes family and is a biennial herbaceous plant with green leaves as its main product. Spinach can be eaten cold, stir-fried or made into soup. It is used for canning in some European and American countries and is the main green leafy vegetable. Spinach likes cool temperatures and is intolerant of high temperatures and strong light. Generally, spinach will have difficulty growing normally when the temperature exceeds 25 degrees Celsius. "Seed soaking and germination" When the temperature reaches 30 degrees Celsius, it is difficult for spinach seeds to germinate.

Cilantro (an alias for turnip, also known as coriander and coriander) is an annual herbaceous plant of the Apiaceae family, mainly used as a vegetable as a seedling. Whether it is planting coriander in summer or autumn, before sowing, the ground should be leveled and raked, and the coriander seeds must be properly processed. You can put the coriander seeds in a dustpan and rub the seeds with the soles of your shoes. This will not only increase the number of plants, but also The germination rate is high. After rubbing, soak it in warm water for two days, then plant it on the ground, bury it in soil, water it well, and cover it with plastic film or a straw curtain. If there is a drought, water frequently to keep warm and moisturize, so that buds will grow early and seedlings will emerge early. Practice has proven that using this method will allow seedlings to emerge 15 days earlier than the old method.

Don’t plant the seeds of Chinese cabbage too deep, otherwise it will be difficult for the seeds to break through the soil and grow.

There is so much knowledge on the Internet! It made me dazzled. There was a lot of knowledge that I didn’t understand, such as "chromosomes", "bolting", "leveling and rake", "soaking seeds and germinating", etc. We went to ask Teacher Dong in the science class, and Teacher Dong told us, "We are here." Learn by doing, do a little bit to understand it, okay?” In fact, we are also eager to do actual experimental research!

4. Do it by hand and experience planting

Finally the weekend is coming, and everyone is busy working separately. I came to school early on Monday and found two plastic bags of soil and two plastic bags of feces on the ground. We are really excited to think that we will start planting soon.

On September 14th, everything is ready to start. It's a sunny day. Teacher Dong first asked us to talk about what we plan to plant? We already knew it, so we just put soil in the pot, buried the seeds, watered them, and waited for the seedlings to emerge. It's not that simple to do in practice. Although we only planted eight pots, we went through the following steps:

①. Pour out the manure. Pour the fermented manure (dung that has been fermented at high temperature like soil and has no smell like soil) out of the plastic bag. We used a digging shovel to dig through it several times, smashing all the large pieces of manure into pieces, and picking out the stones. It was easy to watch the teacher demonstrate, but when we started to use our hands, we felt that we were clumsy, and the manure was poured evenly. . The seeds will be very comfortable inside.

② Mixing the soil, no need to ask, the soil also has to be handled in this way. Without waiting for the teacher to teach me, I got the root digging shovel first: turning the soil, breaking the soil clods, and picking out debris.

③. Mix evenly: The teacher gave us a question: How to mix the manure and soil evenly quickly and effortlessly? We discussed it and put the dung and soil on top of each other first, then turned them up and down. The effect is good, the teacher praised us for "using our brains when encountering problems."

④. Installing the pot: First plug the holes in the bottom of the pot with stones (this is what we met earlier, it can seep through (to remove excess water without washing away the soil), then fill the pot with soil. Since the water content in the soil is not high, you can also pat it with your hands after each layer (5---10 cm) (it feels like patting a child). Fill each pot with the same amount of soil, about 2 cm from the edge of the pot.

⑤. Sowing: Take out the seeds that Teacher Wang and we bought from the seed company. After taking out all the seeds, they have a special fragrance, and the seeds of coriander are the most fragrant. Coriander seeds are hemispherical and covered with a thin layer of peel; chrysanthemum seeds are elongated and two to three millimeters long; spinach seeds are small round grains with a black outer skin; and pakchoi seeds are similar to coriander seeds. Carefully spread the seeds evenly in the pot. Teacher Wang specifically said that the coriander seeds should be crushed. Li Han rubbed the coriander seeds several times until they became hemispherical. Then, the four groups of us each took a small handful of their own two pots and spread them evenly on the soil.

⑥ Watering: We all poured mineral water into one pot and tap water into the other. In order to water the same amount, we took a measuring cylinder and a beaker. Teacher Dong told us "the first time Water enough, and then water at the same time when there is a shortage of water, and keep a record. "We watered 500 ml. When we saw that it was not enough, we watered another 1000 ml before it was fully watered, so we watered each pot. 1500 ml.

⑦. Cover with soil. Sprinkle a layer of fine soil evenly on the seeds. Small seeds should be covered with less soil, and large seeds should be covered with thicker soil.

⑧. Cover with a colorless and transparent plastic film on the pot mask, which can not only prevent water from evaporating, but also increase the soil temperature, which is conducive to seed germination and seedling emergence.

⑨. Labeling. We use eight identical flower pots, covered with the same plastic film. Labels must be attached so that we can identify which pot is growing what.

We are really tired after being so busy. But seeing the neatly arranged flower pots on the windowsill, thinking about the seeds sleeping comfortably in the soil, and looking forward to the appearance of the seedlings emerging from the ground, we felt happy.

5. Focus on observing vegetable seedlings

Observing the emergence of seedlings:

On September 15, we thought when we got up in the morning that my plant babies would not Knowing whether it came out or not, Zhang Dongxu said to himself even while eating: "This seed is so delicious!" Zhang Dongxu's mother was very surprised and said: "What kind of seed?" "No, it's a vegetable." Zhang Dongxu said. Zhang Dongxu's mother said again, "What are you thinking about?" Zhang Dongxu said, "Seed Baby" and then went to school with his schoolbag on his back. We came to school early, and the first thing we did was to take a look at the vegetables we grew. To our disappointment, none of the vegetables sprouted. On September 16, we went to see our seed baby again, but there was still no change. Miao Rui came home and asked her grandma, "How many days will it take for spinach to grow tiny teeth?" Her grandma said, "It takes more than 20 days." It takes more than 20 days, it’s so long!” On September 17, the pak choi in Zhang Dongxu’s group sprouted, and the green seedlings were working hard to grow upward. The students in their group cheered and jumped for joy. Zhang Dongxu’s voice is louder than before. The students in our other groups are so envious and jealous! On September 18th, we thought that all the seedlings in Zhang Dongxu's group had sprouted, and the seedlings in our group should also grow. We prayed, and I walked to the flowerpot with my eyes covered, and suddenly opened my hand. A miracle happened, and the seedlings grew. ! It was tender green, like lively and cute little dolls. They looked up at us. I touched the soil and found it was dry, so I poured half a bottle of water on them. They really made me happy. ah! Looking at the coriander in the Li Han group and the spinach in the Miao Rui group, they have also sprouted, and little green heads have grown out one after another. These seedlings are so cute, and we cheered with joy.

Observe vegetable seedlings rotating with the sun

In today’s science class, we learned about the phototropism of plants. That is: every plant turns toward the sun. I was going to observe the vegetables we planted. At the end of get out of class today, I secretly turned all the pots 180 degrees, waiting for a miracle to happen. The next morning I came to school and looked at the flower pots. A miracle really happened. The direction of the plants changed. There are beautiful stories everywhere in nature!

If the vegetable seedlings have grown too much, they need to be thinned out

On September 28, when the vegetables grew to 2-3 cm high, the teacher asked us to pull out part of the crowded vegetables. We felt it was a pity and asked why, and the teacher said: "In the process of growing, plants need to receive sunlight and produce nutrients. In other words, plants, like people, can't breathe when they are too crowded. They cannot grow if they are too crowded, and they may even die. So we need to thin out and stabilize the seedlings. We will also learn about photosynthesis of plants in the future, and you should study hard at that time!" We thinned out and stabilized the coriander seedlings according to the teacher's instructions. My chrysanthemum should be about 3 centimeters long, Zhang Dongxu’s pakchoi should be about 10 centimeters long, Li Han’s coriander should be about 1 centimeter long, and Miao Rui’s spinach should be about 3 centimeters long. We spent the time before the microcomputer class thinning out seedlings together. With the help of Teacher Wang, I left a relative number of seedlings in each pot, and they are much neater now. I took a bite of the weight loss. Um! Very fragrant, much better than the ones you buy. I tasted the food from three other classmates and it was also very delicious. In short, it was better than the food bought from the vegetable market. At this time, I thought of a saying: "Eat the bitter, the bitter, the sweet." In other words, although we are tired from growing this, we still gain something from eating delicious vegetables. The vegetables after thinning and setting seedlings look very sparse at first, and you can see the soil in the pot. But after a day, you can no longer see the soil in the pot, and they look much neater. After a few days, you will find that various vegetable seedlings have grown. It is taller, the stems have become thicker, and the leaves are black and oily. We are ecstatic.

Comparing the two pots, there are differences

On September 30, I took a ruler to connect the chrysanthemum chrysanthemum among us, and found that the plant in the pot with tap water grew very short, while the plant in the pot with mineral water grew very short. But it is very tall and strong. This shows that the nutrition of mineral water gives Chrysanthemum chrysanthemum strength. Moreover, not only Chrysanthemum chrysanthemum likes mineral water, the results of the students who studied with me also showed that the pot filled with mineral water grew significantly better than the one poured with tap water. high. This shows that mineral water is better for watering flowers. So we asked Teacher Dong with this question. Teacher Dong asked us to check the information about the ingredients contained in mineral water. So we checked the information again and found: "Generally speaking, it just gushes out from the ground and does not require artificial processing or filtering." Only clean water can be called natural mineral water. If clean underground water is extracted artificially and sterilized appropriately, it is called "general mineral water." "Tap water does not contain as much minerals as mineral water. However, Tap water contains chlorine and fluoride. Chlorine is used for sterilization, and fluoride prevents tooth decay.” The trademark ingredients of the “Master Kong mineral water bottle” we poured read “purified water, magnesium carbonate and potassium chloride”. We checked. "Potassium chloride has the effect of lowering blood pressure on the human body; it is a quick-acting potash fertilizer that is easily soluble in water for plants. It contains about 60% K2O and appears as white, light yellow or purple-red crystals. It has good physical properties and can be used as base fertilizer and top dressing. Use. The application of potassium chloride on acidic soil should be combined with lime and organic fertilizers. "It is also found that "the nutrients carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur required by plants are the elements that make up proteins and then protoplasm. In addition to these 6 elements, there are 14 elements that are necessary for some or various plants. They are: calcium, magnesium, potassium, iron, manganese, molybdenum, copper, boron, zinc, chlorine, sodium, cobalt, vanadium and Silicon. Not all plants require all of these elements, but all of them have been found to be necessary for some plants. These mineral elements, together with phosphorus and sulfur, make up what is called plant ash, which is what is left after the carbon, hydrogen, oxygen, and nitrogen have been burned. These 20 elements play an important role in plant growth and development. If their quantity is insufficient, plant growth will be restricted and the yield will be reduced. The carbon, hydrogen, and oxygen contained in plants are obtained through photosynthesis. The action is converted into simple carbohydrates, and ultimately amino acids, proteins, and thus protoplasm. It is generally believed that these elements are not mineral nutrients, and humans can do little to change them except to control water or, to a lesser extent, carbon dioxide. The supply of these elements to plants. The content of mineral elements in plants is affected by many factors, so their contents in crops vary greatly. This should be kept in mind when using the composition data of various elements in plants." According to our investigation. After encountering the information, I found Teacher Dong and said: "The vegetables we watered with mineral water grew taller because we inadvertently added potassium fertilizer and magnesium carbonate to them, which are useful elements for plants. Right?" Teacher Dong encouraged us and said: "You guys This is exploring science. "We have gained a lot of knowledge, and I am so happy!

The trouble caused by the National Day holiday

Time flies so fast! In the blink of an eye, the National Day holiday came, and at this time, the four groups of us began to worry. Let me tell you why I am worried! The vegetables we planted have all grown up, and they are growing very well and green. Maybe everyone wants to say: "Isn't this very good?" It's good, but it's not good. It's a seven-day National Day holiday. Who will water them? However, the weather turned sunny again, because the school asked the head teacher of each class to water the water on Thursday, but Teacher Wang asked another teacher to water the water on Friday instead of her. I was a little worried. Before leaving, I watered both pots. Enough water. On October 8th, the National Day holiday was finally over. When the term started, I came to school. The first thing I did was to see my "little baby", but the result disappointed me. Six or seven of the "little babies" died, and Up to five of the best-growing trees died. I thought, if mine is dead, other people’s may not be alive either. I found that Zhang Dongxu's cabbage was even more fragile, with almost no two alive, and a few of Miao Rui's were dead. But when I saw Li Han's, I was shocked. Li Han's cilantro didn't even have a single one. die. We concluded that coriander is the most drought-tolerant, spinach is the second, chrysanthemum is the third, and Chinese cabbage is the fourth. We were puzzled and reported this matter to Teacher Dong. We said: "Why are not all of them dead? Why do the plants that grow best and those who drink mineral water die the most?" Teacher Dong told us: "This is because the leaves of the plants There are many small holes that we cannot see with our eyes. The plants will turn the water absorbed from the roots into water vapor and run into the air through the small holes, making the indoor air moist and not dry, which is beneficial to the human body. This is called Transpiration of plants.

If it grows well, it will transpire quickly, and the soil in the pot will dry out quickly, so more will die. Please check again to see if there are any other reasons. "We suddenly realized that this is what happened, and we will take better care of plants in the future. After we returned, we found in the "China Fertilizer Network" that "fertilizers containing harmful ions: ammonium chloride, potassium chloride fertilizers, contain a lot of harmful Chloride ions will produce water-soluble compounds after being applied to the soil, which will burn seeds and seedlings; fertilizers such as ammonium nitrate and potassium nitrate contain nitrate ions and have a serious impact on seed germination, so they should not be used as seed fertilizers. "This shows that the mineral water we pour contains potassium chloride, which also has an adverse effect on our vegetables. We told Teacher Dong about this again, and Teacher Dong asked us to do a comparative experiment on seed germination, using water containing potassium chloride. Soak the seeds with tap water to see if there is any effect.

6. Do experiments and observe germination

On October 21, we We did a comparative experiment on seed germination with Teacher Dong. We used water containing potassium chloride and tap water to do a comparative experiment. Under the guidance of the teacher, we carefully observed the shape, color, size, and whether each seed was plump and damaged. , then select 20 seeds of each of chrysanthemum, coriander, spinach and Chinese cabbage from the seed company, put them in eight identical culture vessels, and label two different ones Z and K, to distinguish between tap water and tap water with potassium chloride. First, let them be completely immersed in tap water, and then under the guidance of the teacher, I dropped two drops of potassium chloride solution into the evaporating dish with K. On the window sill of the science office, we also started waiting.

On October 22, we went to the science team to see the seeds in the experiment. After a night of soaking, the seeds have drunk enough water and become round and the seed coat is much thinner. The teacher said that the seeds have drunk enough water and it is time to breathe. We use a straw to suck out the same amount of water and let half of the seeds soak in. In the water, half of them are exposed to the air. The seeds should be kept at a suitable temperature while still being exposed to the air (they should be placed in a sunny place as much as possible). What we are most concerned about is, when will they germinate? Are the germination conditions the same?

On October 24, the seeds of the two evaporating dishes of Chinese cabbage all sprouted. There was no difference. Teacher Dong asked us: "Where are the sprouts?" Where is the bud? "We all pointed to the small white tip on the seed for Teacher Dong to see. Teacher Dong said: "Guess which organ of the plant it will grow into in the future? "I don't know who answered without thinking: "It must have grown into a bud. "In which direction do the buds grow?" "Of course it's up." "The teacher did not make any conclusions and let us observe by ourselves. First, Li Han had a new idea. He said, "This seems to be a root, not a shoot. "We looked for a magnifying glass to observe, and everyone looked at it several times. Because the "buds" of cabbage are the longest, everyone mainly observed the cabbage. It turns out that this little guy has tiny hairs on the top. It's scary to look at it. I thought, is it really a root? I checked on the Internet, and sure enough, it said that the seeds sprout first and have many small hairs on the roots to absorb water and nutrients. At night, the chrysanthemum and coriander also stretched out their roots. The color of the tip is tender and white, but the spinach has not yet grown roots (so-called buds). We think it is because the spinach has a thick seed coat and lacks water, so it grows slowly. I want to peel one off, teacher. I was told not to damage the radicle and cotyledons inside. I opened one and saw the white radicle and green cotyledons. On October 25, I found that the seed I had opened was stretched out. The seeds have not yet sprouted. The roots of Chinese cabbage, chrysanthemum and coriander are growing longer and longer. At this time, the water in the evaporating dish has dried up. We decided to add ten drops of tap water to them every day, plus one drop for those with K. Potassium chloride liquid

On October 18, all the spinach plants also grew white roots, but the plants in pot K were thicker than those in pot Z. We determined that potassium chloride did act as a fertilizer.

On October 23, all the plants in the K pot wilted and died at night. We determined that potassium chloride would indeed burn the seedlings, so it was not suitable to be used as a seed fertilizer. What concentration affects the roots, stems and leaves?

After experiments, we determined that the germination rate of corn is 45℅, millet is 70℅, millet is 40℅, and wheat is 95%. ℅. The germination rate of sorghum is 65℅. Since the rice seeds never germinate, we waited anxiously and patiently. After May Day, we changed the rice seeds and tested the germination rate again.

The following is a seed observation and comparison table of rice, sorghum, corn, wheat, millet, and millet

Chrysanthemum chrysanthemum

Pakchoi

Coriander

Spinach

Shape

Long shape

Round shape

Hemispheric shape

Size

Large

Small

Small

Medium

Color

K

Z

K

Z

K

Z

K

Z

Seed soaking and germination time (days)

2

2

1

2

2

5

5

Young root length per month

(cm)

Germination rate

Death time

7. No effort, no gain< /p>

We have benefited a lot from this activity.

a) It improves our hands-on ability. Through planting, we experience the joy, harvest and joy of labor. We have personally experienced that there is no gain without effort. We also learned a lot of interesting science.

b) We encountered many difficulties in the experiment, which made us truly understand the meaning of "hard-earned". Thinking of the hardships of the farmer uncle, the students unanimously expressed that they must cherish food and cherish other people's food in the future. The fruits of labor.

This experiment is so happy! Everyone is welcome to try it too.